Cone beam CT in dentistry: uses and radiation safety

This post is general education from Copeland Consulting Services. It is not clinical or regulatory advice. It names no products. Follow your state radiation rules and your own clinical judgment.

What is dental cone beam CT?

It is an X-ray system that rotates around the patient and builds a three-dimensional image. The FDA says dental systems capture data with “a cone-shaped X-ray beam” and reconstruct 3D images of the teeth, the oral and maxillofacial region, and the ears, nose and throat. CBCT is a variation of traditional computed tomography.

A conventional image is two-dimensional. The FDA says CBCT offers three-dimensional information, which “may help with the diagnosis, treatment planning and evaluation of certain conditions.”

What is CBCT used for?

The FDA says dental CBCT systems have been sold in the United States since the early 2000s. It lists clinical uses:

• Dental implant planning
• Visualization of abnormal teeth
• Evaluation of the jaws and face
• Cleft palate assessment
• Diagnosis of dental caries
• Endodontic (root canal) diagnosis
• Diagnosis of dental trauma

The ADA adds scenarios from its 2026 recommendations: cracked teeth, endodontics, implant planning and placement, and temporomandibular disorders. For implant topics, see immediate implant placement and guided implant surgery.

How does the radiation dose compare?

Higher than a conventional dental X-ray, and generally lower than other CT. That is the FDA’s summary: “the radiation doses from dental CBCT exams are generally lower than other CT exams, dental CBCT exams typically deliver more radiation than conventional dental X-ray exams.”

The FDA also says concerns are greater for younger patients. They are more sensitive to radiation, and they have more years for ill effects to develop. The FDA defines pediatric patients as birth through 21 years.

The ADA puts dental imaging in context. It says dental imaging is “a minor contribution to the total exposure from all sources.” It cites the National Council on Radiation Protection and Measurements estimate of 6.2 millisieverts (mSv) per year mean effective dose from all sources in the United States, half from natural sources and half from man-made sources. Dental imaging accounts for less than 1 percent of the estimated collective annual effective dose from medical imaging, per the ADA.

When should CBCT be used?

Only when other imaging cannot answer the question. The FDA says: “Dental CBCT should be performed only when necessary to provide clinical information that cannot be provided using other imaging modalities.” It asks dental professionals to apply justification and optimization:

1. Discuss the reason for the exam so the patient understands benefits and risks.
2. Decide whether the exam answers a clinical question, consider options with less or no radiation, and review the patient’s imaging history to avoid duplicates.
3. Use exposure settings that give the lowest dose with image quality adequate for diagnosis.

The ADA gives the same direction. Its list for minimizing exposure includes “incorporating CBCT only when lower-exposure options will not provide the necessary diagnostic information.” The Image Gently program, which the ADA has joined with more than 80 organizations, urges providers to “use cone-beam CT (CBCT) only when necessary.”

What did the ADA change in 2026?

On January 5, 2026, the ADA released what it called its first dental X-ray recommendations in more than a decade. They are the first from the ADA to cover both 2-D and 3-D imaging by clinical scenario. They were co-published with the American Academy of Oral and Maxillofacial Radiology and update 2012 guidance.

The ADA says the recommendations stress a thorough clinical exam before imaging, and that they are “not intended to be standards of care, nor requirements or regulations.” A separate 2024 ADA-convened report no longer recommends thyroid collars for any dental imaging procedure. It says such shielding can block the primary beam and force retakes, and points to rectangular collimation, correct positioning and dose-reduction methods instead.

What do FDA and ADA say about children?

Both stress extra care. The FDA runs a pediatric X-ray imaging site that gives specific recommendations to parents and providers to help reduce unnecessary radiation exposure to children. The ADA’s Image Gently program asks providers to select X-rays for individual needs, not as a routine, to use the fastest image receptor available, to collimate the beam to the area of interest, and to “child-size” the exposure time.

The FDA also suggests that patients and parents ask whether the facility uses radiation reduction techniques such as size-based protocols for children, and whether equally useful exams that use no or less ionizing radiation exist. A practice can prepare plain answers to those questions ahead of time.

What should a practice record and review?

The FDA says to review the patient’s medical imaging history to avoid duplicate exams. Keeping the reason for each scan, the settings used, and the findings in the chart makes that review possible. The FDA also says equipment should be “properly maintained and tested.”

A practice can build these checks into a routine:

1. State the clinical question before ordering the scan.
2. Document why lower-exposure options were not enough.
3. Check for earlier images to avoid repeats.
4. Record the protocol chosen for the patient’s size and the area scanned.
5. Schedule equipment testing as your state requires.

These are practical suggestions. The state radiation program and the ADA documents set the actual rules and recommendations.

What safety steps apply to every scan?

The ADA lists these steps for minimizing exposure:

• Order radiographs based on clinical need, and try to use images from earlier exams.
• Use digital receptors rather than film. See digital radiography.
• Restrict the beam to the area of interest (rectangular collimation).
• Adhere to all federal, state and local radiation safety rules.

State rules set specific requirements for inspection and testing of the facility and equipment. Ask your state radiation program what applies to you. Also see infection control and the dental compliance checklist guide for related duties.

Next step

For purchasing and workflow questions, read the dental technology return-on-investment guide and the dental technology overview. To discuss a related project, contact Dr. Copeland about consulting.